Vehicle airbag deactivation switch with interchangeable cylinders

ABSTRACT

An airbag deactivation system for the airbags mounted in a motor vehicle. The system provides a switch and circuitry to allow for selective deactivation of driver and/or passenger airbags in a motor vehicle via a conventional ignition key inserted into a key cylinder. The switch includes interchangeable key cylinders to allow for limited selective deactivation and a key stop to limit the amount of insertion of the ignition key into the key cylinder. LED&#39;s emit light from the deactivation module when indicating a deactivation condition, which is viewable by both a driver and a front seat passenger. Alternatively, LED&#39;s are mounted in a remote indicator assembly, separate from the deactivation module, to provide improved visual indication to the driver and front seat passenger of the state of airbag deactivation.

FIELD OF THE INVENTION

The present invention relates to automotive vehicle occupant restraintsystems, particularly airbags. It relates more specifically tomechanisms for selectively disabling part or all of those systems.

BACKGROUND OF THE INVENTION

Since inflatable occupant restraint systems or airbag systems have comeinto widespread use in the automotive industry, it has been observedthat there are certain instances in which it may be desirable todeactivate the airbag system, or a portion thereof, in a vehicle duringthe period in which the vehicle is in use. Exemplary of such instancesis that present when a vehicle has airbags for both the driver and frontpassenger positions and a rear facing infant seat is placed in the frontpassenger position, not properly positioned for use with the airbag.Another example is that of a driver who is small in stature and mustoperate the vehicle from a seating position that is very close to thesteering wheel of the vehicle.

Since practically all airbag systems presently in use are activated bytransmitting an electrical signal powered by the vehicle electricalsystem, it has been suggested to provide switching to effectdeactivation of the airbag system, or a portion thereof, on a selectivebasis. U.S. Pat. Nos. 5,324,074; 5,234,228; 5,161,820; and 5,544,914 areexemplary of such approaches.

Certain disadvantages, however, are noted in the prior art disablingsystems. These disadvantages arise from the appropriate desire of thedesigner of the occupant restraint system to ensure that because of theinherent normal benefit of having the airbag system operating, thedisabling takes place only when intended and only under control of theoperator of the motor vehicle. It is also desired that the reliabilityand efficacy of this disabling device be monitored during a vehicleoperating event which might normally give rise to operation of theairbag deactivated by the deactivation system. Further, it is desirablethat one have the flexibility to selectively disable only the desiredairbag(s) in a multi-airbag system.

Further, in order to minimize the cost to vehicle owners, preferably anyairbag deactivation system will be easy and quick to install, generallyusing existing airbag system connections that are in place on a largevariety of airbag equipped vehicles; and will be easily adaptable tovarious vehicles with common parts to further minimize the cost. Also,preferably, any changes to the existing airbag system will not detractfrom the current overall safety of the vehicle due to the newdeactivation equipment.

SUMMARY OF THE INVENTION

In its embodiments, the present invention contemplates an airbagdeactivation system operable by a vehicle ignition key, for use with anairbag restraint system in a vehicle. The airbag deactivation systemincludes an airbag deactivation circuit, adapted to operatively engagethe airbag restraint system, including a switch having at least threeswitch positions. Switch actuation means operatively engage the switch,for selectively moving between three of the switch positions. Also,switch limiting means selectively limit the switch movement of theswitch actuation means to less than all of the at least three switchpositions.

Accordingly, an object of the present invention is to provide an airbagdeactivation system that will selectively deactivate one or more airbagsin a vehicle, when desired.

Another object of the present invention is to provide an airbagdeactivation assembly that is easily adapted to install in a largevariety of vehicles equipped with multiple airbags and will indicate theparticular airbags deactivated.

A further object of the present invention is to provide an airbagdeactivation system that can be selectively configured to allow fordeactivation of only certain airbags within a particular vehicle, butdoes not require a change in the circuitry and connections of thesystem.

An advantage of the present invention is that the airbag deactivationsystem is configurable to provide an optimal viewing location ofdeactivation indicators for both driver and front seat passengers.

Another advantage of the present invention is that the deactivationsystem is switchable with generally any typical ignition key for a lightvehicle, but not generally by children or inadvertently.

An additional advantage of the present invention is that the airbagdeactivation module will maintain a record of the current switch settingduring an airbag actuation event.

A further advantage of the present invention is that a vehicle airbagsystem can still perform a diagnostic check even when one or moreairbags are deactivated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation view of an automotive instrument panelillustrating installation of an airbag deactivation system according tothe present invention;

FIG. 2 is a view similar to FIG. 1 illustrating an alternate embodimentfor installation of the airbag deactivation system;

FIG. 3A is a partially schematic view of an airbag disabling system asapplicable to FIGS. 1 and 2 in accordance with the present invention;

FIG. 3B is a partially schematic view, similar to FIG. 3A, of analternate embodiment of an airbag disabling system;

FIG. 4 is an electrical schematic of a deactivation switching circuitemployed in the system illustrated in FIGS. 3A and 3B in accordance withthe present invention;

FIG. 5 is an alternative representation of the electrical schematic ofthe deactivation circuit of FIG. 4, showing a slightly modifiedconfiguration;

FIG. 6A is schematic side view of a portion of a key and key cylinder inaccordance with the present invention;

FIG. 6B is another side view of the key and a portion of the keycylinder illustrated in FIG. 6A;

FIG. 7 is an elevation view, similar to FIG. 2, illustrating anotheralternate embodiment of the present invention;

FIG. 8 is a partially schematic view, similar to FIGS. 3A and 3B,illustrating the airbag disabling system illustrated in the embodimentof FIG. 7;

FIG. 9 is a view similar to FIG. 8, illustrating another alternateembodiment of the airbag disabling system of FIG. 7;

FIG. 10 is a electrical schematic diagram corresponding to the airbagdisabling system illustrated in FIGS. 8 and 9;

FIG. 11 is a schematic diagram illustrating an arrangement of connectorsfor the airbag deactivation system illustrated in FIGS. 8 and 9;

FIG. 12 is a plan view of a portion of a bezel and key cylinder inaccordance with an additional embodiment of the present invention;

FIG. 13A is a partially exploded perspective view of a key cylinder inaccordance with the present invention;

FIG. 13B is a view of the key cylinder taken in the direction of arrow13B in FIG. 13A;

FIG. 13C is a sectional view taken along line 13C--13C in FIG. 13A;

FIG. 13D is a view taken in the direction of arrow 13D in FIG. 13B;

FIG. 13E is a sectional view taken along line 13E--13E in FIG. 13B;

FIG. 14A is a front view of an airbag switch plate in accordance withanother embodiment of the present invention;

FIG. 14B is a sectional view similar to FIG. 13E illustrating theembodiment of FIG. 14A;

FIG. 15A is a view similar to FIG. 14A illustrating a differentembodiment of the present invention;

FIG. 15B is a sectional view similar to FIG. 13E, illustrating theembodiment of FIG. 15A;

FIG. 16A is a view similar to FIG. 14A illustrating another embodimentof the present invention; and

FIG. 16B is a sectional view similar to FIG. 13E illustrating theembodiment of FIG. 16A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates an instrument panel 20 of an automotive vehicleincluding a main body portion 22 having a center section 24 in which ismounted an airbag deactivation system 26 according to the presentinvention. FIG. 2 differs slightly from FIG. 1. The embodiments of FIGS.1 and 2 differ in that the instrument panel 20 of the FIG. 1 embodimentincludes the airbag deactivation system module 26 mounted directly intothe main body portion 22. On the other hand, the FIG. 2 embodimentillustrates an instrument panel 28 having a main body portion 30 and anairbag deactivation system module 32 positioned to suspend below themain body portion 30. Hereinafter, since the difference between the FIG.1 embodiment and FIG. 2 embodiment is just the mounting location of theairbag deactivation system modules 26,32, when referring to thecomponents in the FIG. 1 embodiment, the FIG. 2 embodiment will not bespecifically referenced, although the discussion will also apply. Ineither case, the location of any indicators for the airbag deactivationare preferably such that they are viewable by both the driver and anyfront seat passenger.

It is contemplated the that deactivation system module 26 is bestutilized in automotive vehicles that have airbag assemblies installed inat least two seating positions in the front seat of a vehicle; an airbagassembly 38 in a steering wheel 40 protruding from the instrument panel20, and an airbag assembly 42 generally in front of the passengerposition(s) in the front seat of a vehicle. When the front passengerseat the passenger airbag assembly 42 is unoccupied or is occupied bypersons or things for which operation of the airbag system is notdesired, then it is advantageous to deactivate this airbag assembly 42.

Some exemplary uses are the deactivation of the passenger airbagassembly 42 in situations in which an infant in a rear facing child seatis placed in the front passenger position, or when a small child isplaced in this seating position. It may be desirable, then, todeactivate the passenger airbag assembly 42. Another example is asituation where a person of very small stature is operating the vehicle,and will be in such a position that this person must operate the vehiclewhile in very close proximity to the driver airbag assembly 38. In thissituation, it may be desirable to deactivate the driver side airbagassembly 38. A combination of the above examples, or other conditions,may also warrant a desire to selectively deactivate both the passenger42 and driver 38 airbag assemblies.

The configuration of the airbag deactivation module 26 and airbagassemblies 38,42 for that illustrated in FIG. 1 can best be seen in FIG.3A. An airbag diagnostic module 44 is connected to a wiring harness 43and includes electrical wires 45 extending therefrom in the direction ofthe airbag assemblies 38,42. This arrangement is typical of an airbagsystem whether or not is has a deactivation mechanism. The airbagdeactivation module 26 includes a housing 46, which mounts to theinstrument panel 20, with a bezel 48 mounted to the front of the housing46. The bezel 48 includes an opening, through which a key cylinder 50protrudes, and two indicator lights 52,54, one on either side of the keycylinder 50. Within the housing 46 is an interface connector module 55which receives the wires 45 from the diagnostic module 44 and includeselectrical wires 56 extending therefrom to the airbag assemblies 38,42.Also, power 57, from the ignition, and a ground 59 connect through themodule 55.

For this embodiment, the wires are illustrated with splices 58 in them.This configuration illustrates a deactivation system 26 which is addedto a vehicle after production. This configuration allows for theaddition of the deactivation system 26 with minimal splicing of wiresand no need to splice into a large wire harness. The location of thesplices 58 (connectors) will help to minimize the work required toinstall the system. If the deactivation system 26 is designed into theparticular vehicle prior to production, then the splices of course wouldnot be needed. The wires extending between the connector module 55 andsplices 58, then, form an overlay harness 47, which allows foradjustment to different vehicle specific wiring configurations. Thisallows for the one switch to be adapted to many vehicles.

FIG. 3B illustrates an alternate embodiment of the airbag deactivationmodule 26 of FIG. 3A in that the interface connection module 60 is nowlocated outside of the housing 46. It connects directly to the wiringharness 43 in the same way as the airbag diagnostic module 44 in FIG. 3Aand in the same way as do vehicles without any deactivation circuitry.The interface connection module 60 includes wiring 64 extending to thehousing 46 and wiring 66 extending to the airbag diagnostic module 44.The other wires 62 now extend from the wire harness 43 to the airbagassemblies 38,42 without any splices. For this embodiment, a vehiclewith an existing airbag system can be retrofitted with the deactivationcapability without having to splice into the wiring harness connected tothe airbag system or to the wiring connecting to the airbags 38,42themselves, thus minimizing the installation effort. The only part,then, that needs to adapt for different vehicles is the interfaceconnection module 60, with the other components generally being commonto various systems.

FIG. 4 illustrates the electronics behind the deactivation switch, whichis mechanically operated by the key cylinder 50. The three boxesillustrated in FIG. 4 indicate parallel circuitry on the same switch,with the leftmost box indicating the circuitry for controllinglight-emitting diode (LED) indicators, the middle box indicating thecircuitry for the driver airbag deactivation settings and the right boxindicating the circuitry for the passenger airbag deactivation settings.The switch 72 is a four position, three pole switch actuated by rotationof the key cylinder 50, shown in FIGS. 3A and 3B.

Viewing the leftmost box in FIG. 4, a first switch position 74corresponds to a driver and passenger airbags on condition, while asecond switch position 78 corresponds to a driver off (deactivated) anda passenger airbag on condition. A third switch position 80 correspondsto a driver on and a passenger off (deactivated) airbag condition, whilea fourth switch position 76 corresponds to a driver and passengerairbags off (deactivated) condition.

The base 82 of the switch 72 is connected to a source of power that isactivated when the vehicle ignition is on. For the first switch position74, the power connects to none of the LED's, so no light will be emittedfrom the airbag deactivation module 26 (illustrated in FIGS. 1-3B). Whenthe switch 72 is in the second switch position 78, a driver-off LED 84will be activated. This LED 84 is positioned, as seen in FIG. 3A, behindthe indicator light opening 52, to indicate to the vehicle operator thatthe driver side airbag assembly is deactivated. When the switch 72 is inthe third switch position 80, a passenger-off LED 86 will be activated.This LED 86 is positioned, as seen in FIG. 3A, behind the indicatorlight opening 54, to indicate to the vehicle operator that the passengerside airbag assembly is deactivated. Diodes 88 and 90 isolate the driverand passenger airbag circuits.

At the same time that the movement of the switch 72 effects changes inthe activation of the LED's, it also effects deactivations of the airbagassemblies. The middle box in FIG. 4 illustrates the driver airbagassembly deactivation circuit. The base 92 of the switch 72 connects toa return line, for the driver airbag assembly, to the airbag diagnosticmodule. When the switch 72 is placed in a first switch position 94 or athird switch position 96, the switch 72 connects to a return line 99from the airbag system for the driver airbag assembly. In thesepositions, the driver airbag assembly is active.

When the switch 72 is placed in an second switch position 98 or a fourthswitch position 100, the return line to the airbag diagnostic module isnow connected, through a combined resistor-fuse 102, between a feed line104 from the airbag system and a feed line 106 to the airbag diagnosticsmodule for the driver airbag assembly. The driver airbag assembly is nowdeactivated, but the resistor-fuse 102 is connected to the system toallow for current flow during diagnostic checks on the driver airbagsystem.

The right box in FIG. 4 illustrates the passenger airbag assemblydeactivation circuit. The base 108 of the switch 72 is electricallyconnected to a return line, for the passenger airbag assembly, to theairbag diagnostic module. When the switch 72 is placed in a first switchposition 110 or a second switch position 112, the switch 72 iselectrically connected to a return line 114 from the airbag system forthe passenger airbag assembly. In these two positions, the passengerairbag assembly is active. When the switch 72 is placed in a third 116or a fourth 118 switch position, the return line to the airbagdiagnostic module is now connected, through a combined resistor-fuse120, between a feed line 122 from the airbag system and a feed line 124to the airbag diagnostics module. The passenger airbag assembly is nowdeactivated, but the resistor-fuse 120 is connected to the system toallow for current to flow during diagnostic checks on the passengerairbag system.

When the switch 72, then, is in the fourth switch positions 76,100,118,the LED's will be activated and the current will flow through theresistor-fuses 102,120 rather than through the return lines 99, 114,thus disabling both the driver and passenger airbag assemblies.

FIG. 5 is an alternative way to illustrate the switch circuit of FIG. 4,with an alternate arrangement for the LED's also shown. The circuit iscontained within the housing 46. Two of the bases 92,108 of the switch72 connect through the airbag diagnostic module 44 to an airbagactuation switch 122. The airbag actuation switch 122 will not bediscussed further since it is part of the overall airbag system and doesnot form a part of the present invention. This circuit illustrates theLED's 84,86 discussed in relation to FIG. 4, and two additional LED's124,126, each one in parallel with one of the others. This arrangementallows for a backup so that if one LED malfunctions, the other inparallel with it will still light, allowing the driver and front seatpassenger to still note visually that a particular airbag assembly isdeactivated.

This figure illustrates how the switch 72, during airbag deactivation,will divert the current from the firing mechanisms 128,130 of the airbagassemblies 38,42, repectively; through the resistor-fuses 102,120. Theresistor-fuse elements 102,120 are referred to as such because in thiscircuit they not only act as fuses that will open at a predeterminedlevel of current, but these fuses are designed to have a predeterminedresistance. It is known to apply low power to airbag systems to test theintegrity of the systems. The circuit diagnosis effected during suchoperation makes use of the resistance of certain of airbag electricalcomponents, such as the firing mechanisms 128,130. With an airbagassembly deactivated however, the resistance of the particular firingmechanism 128 or 130 will no longer be connected to the circuit. Inorder to account for this, the fuse 102 connected through the driverside of the circuit has a resistance which matches the resistance of thefiring mechanism 128, and the fuse 120 connected through the passengerside of the circuit has a resistance which matches the resistance of thefiring mechanism 130. With this arrangement, the diagnostic check canstill be performed, even when one or both of the airbag assemblies 38,42is deactivated.

For the operation of the circuit illustrated in FIG. 4, the switch 72moves the flow of electrical power from the airbag assemblies 38,42 toan alternative position in which the electrical power is supplied to onepair or both pairs of the LED indicators, and one or both of the fuses.During engine start, a low current level test load is run through thecircuit, and a diagnostics check is performed. During vehicle operation,should the airbag sensing system (not shown) determine an airbagdeployment event has occurred, not discussed further herein as anyconventional airbag sensor system may be employed, the switch 122 isclosed and a relatively high current is delivered through the circuit.The current is of course high enough to cause the firing mechanisms 128,130 to deploy the airbags so long as the airbag switch is not set todeactivate them at the time of the event. Advantageously, the fuses102,120, if connected by the circuit due to the switch position at thetime of the event, are sized to disconnect below the level of currentthat the airbag system utilizes to activate the airbag assemblies 38,42.The fuses 102,120, then, act as a memory so that if an airbag firingevent has occurred that effects an airbag firing situation, one or bothof the fuse 102,120 will operate to open the circuit, depending uponwhich airbag assemblies are deactivated at the time, and it can bereadily detected that the switch was in a position where the driver,passenger or both airbags were deactivated.

FIGS. 6A and 6B illustrate the key cylinder 50 and a key slot 136, whichextends into the key cylinder 50. The key cylinder 50 is mounted in theairbag deactivation module housing and is rotatable relative thereto. Italso extends through the front face of the bezel 48. The key slot 136 issized to accept a typical ignition key 138 for a motor vehicle. The key138, upon partial insertion into the key slot 136 permits rotationalmovement of the key cylinder 50 between the four airbag deactivationpositions. It will be noted that the key slot 136, in its longestdimension, will align with the corresponding text for the particulardeactivation condition it is in (as seen in FIGS. 1-3B), giving thevehicle driver and front seat passenger an additional visual indicationof the state of the airbag deactivation, in addition to the LED's. Thekey cylinder 50 is operatively connected in a mechanical fashion to thecircuits indicated in FIGS. 4 and 5 for controlling the position of theswitch 72. The purely mechanical switch arrangement for the deactivationsetting will assure that the deactivation setting chosen stays in thatposition even when vehicle is turned off or stalls, which avoids anyconcern with the deactivation settings changing if a stall situationoccurs during vehicle operation.

While this key arrangement is operable with any typical vehicle ignitionkey, as is preferred, it can be configured to operate only with a keyhaving the shape for a particular manufacturer, if so desired. Moreover,the configuration illustrated in FIGS. 6A and 6B will allow the cylinderto be rotated by inserting any flat object with the general dimensionsof the tip 140 of an vehicle ignition key. The reason for allowing thisflexibility is to allow one who wishes to change the setting to be ableto purposefully do so, although generally one will accomplish the changewith an ignition key. However, the key cylinder 50, by requiring atleast the insertion of some object into the key slot, will prevent thedeactivation mode from being changed inadvertently, as could happen ifone were to configure the deactivation module with merely a handoperable switch or button. Further, the requirement for insertion of akey like object will prevent children from playing with the deactivationsetting and changing it to a position not desired by the vehicleoperator.

Additionally, the key slot 136 includes a key stop 142, which onlyallows a key 138 to extend a short distance into the key slot 136 beforeit abuts the stop 142. The shallow distance that the key stop 142 isrecessed into the key slot 136 is such that a typical ignition key 138,if relased from ones hand while in the slot, will fall out. Thus, anignition key 138 cannot be left in the slot, which would effectivelyconvert it to a hand operated switch or button.

There are two reasons why it is desirable for the key 138 to fall out ifnot supported in ones hand. The first was discussed above in that it isnot desirable to allow children, or others not authorized, to change thesettings without the driver knowing of this. Second, depending upon thelocation of the key cylinder 50 on the instrument panel (some potentiallocations illustrated in FIGS. 1 and 2), it may not be desirable to havea key protruding from the key slot 136 in the instrument panel duringvehicle operation. This may create a hard point that one may potentiallyimpact during a sudden deceleration of the vehicle.

FIGS. 7 and 8 are similar to FIGS. 2 and 3A, only illustrating analternative embodiment. For this embodiment, an additional remoteindicator assembly 146 is provided and electrically connected to the LEDportion of the circuits illustrated in FIGS. 4 and 5. Tie changes to theLED portion of the circuit, for this embodiment, are illustrated in FIG.10.

The remote indicator assembly 146 does not include any of the switchingfunctions or key cylinder 50, and so is much thinner and more compactthan the airbag deactivation module 26. This thinness and compactnessallows for more flexibility in determining where the remote assembly 146is mounted, to assure to the greatest extent possible that both thedriver and front seat passenger can view the current state of the airbagdeactivations. This allows for more flexibility in locating the airbagdeactivation module 26 within the passenger compartment of a vehicle.Further, it does appear similar to the module 26 in that its has a frontbezel 147 with a very similar appearance to the main bezel 48 so as tobe easily recognizable by occupants from different vehicles.

In this embodiment, the module 26 is illustrated mounted within theglovebox 148 of the instrument panel 20. Consequently, while one mayopen the glovebox door 150 when a change in deactivation settings isdesired, with the door 150 closed, neither the vehicle operator nor thefront seat passenger will be able to see the airbag deactivation module26. In order to account for this, the remote indicator assembly 146includes LED's, a first pair of LED's 152 for the driver deactivationindication and a second pair of LED's 154 for the passenger deactivationindication, as illustrated in the schematic circuit of FIG. 10. Thecircuitry illustrated in this figure can be seen to generally correspondto that illustrated in the schematic circuit of FIG. 5 relative to theLED's. The first pair of LED's 152 is connected via wiring 156 to theLED's 84,124 in the main module 26, while the second pair 154 isconnected via the wiring 156 to the LED's 86,126. In this way, when someor all of the LED's 84,86,124,126 in the main module 26 are activated,the corresponding pairs of LED's 152,154 will be activated in the remoteassembly 146.

The first pair of LED's 152 are located behind the driver indicator 158,and the second pair of LED's 154 are located behind the passengerindicator 160. The illuminated indicator(s), then, will allow the driverand front seat passenger to easily determine the deactivation state ofthe airbags. Having two LED's per indicator light is meant to assurethat if one LED becomes inoperable, the indicator will still be able toindicate a deactivation state of an airbag.

Also of note, the wiring 156 splits off from wiring 157, which extendsthrough a connector 159 to the splices 58. Wiring 156 includes a splicelocation held together by a connector 162. This connector 162 providesfor flexibility of mounting the overall assembly in different vehicleswith only minimal changes in the basic hardware, as is discussed belowin regard to FIG. 11.

FIG. 9 illustrates an alternate embodiment to FIG. 8, with thedifferences being similar to the differences in configuration betweenFIGS. 3A and 3B. The remote indicator assembly 146 and the circuitry isthe same, but instead of splices 58, as in FIG. 8, an airbag systemconnector 164 is connected between the original wiring harness 43 andthe airbag diagnostic module 44.

FIG. 11 illustrates the connection between the airbag module 26 andremote indicator assembly 146, as illustrated in FIGS. 8 and 9. Theconnector 162, which electrically connects up the indicator assembly 146not only provides a location where different lengths of wiring 156 canbe used, depending upon the locations of the remote 146 and module 26 ina particular vehicle, but also allows for the flexibility of configuringone module 26 for use with many different vehicle applications. Forthose vehicles which need a remote 146, wiring 156 is connected to theconnector 162 during installation, while for those vehicles where noremote 146 is required, a cap 166 is provided to close off connector162. Thus, the wiring need not change for a vehicle needing a remote andone not needing a remote. Again, this allows for the production of justone main deactivation module 26 for installation in many differentvehicles.

FIG. 12 illustrates the bezel 48 as it sits in front of the vehicleinstrument panel 20. This figure illustrates again how the same basicairbag deactivation module 26 can be accommodated in many differentvehicles, even with instrument panels that have different contours atthe location where the deactivation module 26 is mounted. A foam gasket170 is mounted between the instrument panel 20 and the bezel 48, whichwill allow the assembly to conform to different instrument panelsurfaces.

FIGS. 13A-13E illustrate the key cylinder 50 employed with the previousembodiments discussed above. The key cylinder 50 inserts into an opening174 in a switch support portion 175 of the housing 46. The opening 174is generally of a diameter that is larger than an outer cylindricalportion 176 on the key cylinder 50, but also includes two smallerdiameter portions 178, which in this particular embodiment each areabout 15 degrees wide, with about 165 degrees between each one. The endsof these smaller diameter portions 178, form stops 180.

Affixed to the front of the cylinder 50 is a key face 182, whichincludes the key slot 136, through which a key is inserted when it isdesired to change the deactivation setting. An arrow is formed in itsfront face to provide a visual indication to the cylinder orientation,and thus switch position.

The back wall of the key cylinder 50 forms the key stop 142, and sinceit is desirable to limit the extent to which a key can be inserted, asdiscussed above in relation to FIGS. 6A and 6B, the depth of the keycylinder 50 is much less than the length of a typical ignition key. Thisnot only serves to accommodate the desire to prevent keys from beingleft in the key slot 136, but also keeps the overall depth of the airbagdeactivation assembly to a minimum, thus maximizing the locations whereit can be installed in various vehicles.

Extending from the outer cylindrical portion 176 are first and secondrotation control tabs 184, 186, respectively, with each having a widthof about 30 degrees. The left edge, as seen in FIG. 13E, of the firstrotational control tab 184 is about 15 degrees clockwise from a verticalaxis and the right edge of the second control tab 186 is adjacent thevertical axis. The control tabs 184,186 have an outer diameter which islarger than the smaller diameter portions 178 on the switch portion 175,and so will abut the stops 180 when rotated to certain orientations.Thus, the rotational travel of the key cylinder 50 relative to theswitch portion 175 is limited. The dimensions are set such that thelimits of the rotation will allow for the switching between the fourpositions on the switch. In this case, about 45 degrees counterclockwisefrom the airbag-on position and about 90 degrees clockwise, as can beseen in FIGS. 3A and 3B. A switch control tab 188 interfaces with theswitch 72, illustrated in FIGS. 4 and 5, to mechanically control theswitch settings.

FIGS. 14A and 14B illustrate an alternate embodiment of the key cylinderof FIGS. 13A-13E. For this embodiment, the key cylinder 192 is generallythe same as with the embodiment of FIGS. 13A-13E, except that therotation control tabs have changed. The first rotational control tab 194now extends from about 15 degrees to the left of the vertical axis asviewed in FIG. 14B to about 75 degrees to the right of the verticalaxis. The second rotational control tab 196 now extends from about 30degrees below the horizontal axis on its left end to about 30 degrees tothe right of the vertical axis on its right end. This cylinder isotherwise the same as that in FIGS. 13A-13E and assembles into the otherswitch parts, which remain unchanged, except for the bezel, discussedbelow. The key cylinder 192, with the changed control tabs 194,196, isnow configured to only allow for passenger airbag deactivation. Thecontrol tabs 194,196 will hit the stops 180 before the switch reachesthe driver-airbag deactivation or both-airbag deactivation positions.

Since only passenger airbag deactivation is possible with this keycylinder 192, an alternate bezel 198 is employed to indicate such to thedriver and front seat passengers. While the cylinder 192 and the bezel198 change, all of the other components of the deactivation assemblyremain the same, thus allowing for flexibility in determining whatdeactivations will be possible for a particular vehicle when installed,while maintaining simplicity and minimizing the overall cost for thevarious alternate possibilities. Thus, the electrical circuit andswitching mechanisms do not change even though, for this embodiment, allfour switching positions are not used.

FIGS. 15A and 15B illustrate another alternate embodiment of the keycylinder of FIGS. 13A-13E. For this embodiment the rotational controltabs have changed so that only the driver airbag deactivation ispossible, not the passenger only or the driver and passengerdeactivations. The first rotational control tab 200 now extends on itsleft end, as viewed in FIG. 15B, about 15 degrees to the right of avertical axis to about 15 degrees below a horizontal axis on its rightend. The second rotational control tab 202 now extends on its left endadjacent a horizontal axis, to its right end adjacent the vertical axis.A bezel 204 now indicates the only two available positions. Again, aswith the embodiment of FIGS. 14A-14B, the rest of the deactivationsystem does not change.

FIGS. 16A and 16B illustrate a further alternate embodiment of the keycylinder of FIGS. 13A-13E. For this embodiment the rotational controltabs have changed again, and now will only allow for driver or passengerairbag deactivation, but not both. The first rotational control tab 206now extends on its left end, as viewed in FIG. 16B, from about 15degrees to the right of a vertical axis to about 15 degrees from ahorizontal axis on its left end. The second rotational control tab 208now extends on its left end from about 30 degrees below the horizontalaxis to about adjacent with the vertical axis on its right end. A bezel210 now indicates the only three available positions.

Consequently, by ordering the switch positions and designing the keycylinder to allow for the interchangeability of the cylinders andbezels, as illustrated in FIGS. 13A-16B, one can limit the airbagdeactivation combinations, during the installation of the system, tothose required, depending upon customer and regulatory needs. At thesame time, the rest of the deactivation assembly, other than the keycylinders and bezels, may remain the same.

While certain embodiments of the present invention have been describedin detail, those familiar with the art to which this invention relateswill recognize various alternative designs and embodiments forpracticing the invention as defined by the following claims.

We claim:
 1. An airbag deactivation system operable by a vehicleignition key, for use with an airbag restraint system in a vehicle, theairbag deactivation system comprising:an airbag deactivation circuit,adapted to operatively engage the airbag restraint system, including aswitch having at least three switch positions; switch actuation means,operatively engaging the switch, for selectively moving between three ofthe switch positions; and switch limiting means for selectively limitingthe switch movement of the switch actuation means to less than all ofthe at least three switch positions.
 2. The airbag deactivation systemof claim 1 wherein the switch actuation means includes a first keycylinder interchangeably connected to the airbag deactivation circuitand rotatable to effect movement between the three switch positions, andthe switch limiting means includes a rotation control tab protrudingfrom the key cylinder to limit the extent of rotation of the keycylinder.
 3. The airbag deactivation system of claim 2 further includinga first interchangeable bezel mounted adjacent the key cylinder havingindications thereon indicating the rotational location of the threeswitch positions.
 4. The airbag deactivation system of claim 2 whereinthe rotation control tab limits the extent of rotation of the keycylinder such that movement can only be effected between two of thethree switch positions.
 5. The airbag deactivation system of claim 4further including a second interchangeable bezel mounted adjacent thekey cylinder, having indications thereon indicating the rotationallocation of the two switch positions.
 6. The airbag deactivation systemof claim 1 wherein the switch has four switch positions and the switchactuation means operatively engages the switch for selectively movingbetween the four switch positions and selectively limiting the switchmovement to less than all of the four switch positions.
 7. The airbagdeactivation system of claim 6 wherein the switch actuation meansincludes a first key cylinder interchangeably connected to the airbagdeactivation circuit and rotatable to effect movement between the fourswitch positions, and the switch limiting means includes a rotationcontrol tab protruding from the key cylinder to limit the extent ofrotation of the key cylinder.
 8. The airbag deactivation system of claim7 further including a third interchangeable bezel mounted adjacent thekey cylinder having indications thereon indicating the rotationallocation of the four switch positions.
 9. The airbag deactivation systemof claim 7 wherein the rotation control tab limits the extent ofrotation of the key cylinder such that movement can only be effectedbetween two of the four switch positions.
 10. The airbag deactivationsystem of claim 9 further including a second interchangeable bezelmounted adjacent the key cylinder, having indications thereon indicatingthe rotational location of the two switch positions.
 11. The airbagdeactivation system of claim 7 wherein the rotation control tab limitsthe extent of rotation of the key cylinder such that movement can onlybe effected between three of the four switch positions.
 12. The airbagdeactivation system of claim 11 further including a firstinterchangeable bezel mounted adjacent the key cylinder, havingindications thereon indicating the rotational location of the threeswitch positions.
 13. An airbag restraint system for use in anautomotive vehicle operable by a vehicle ignition key comprising:anairbag restraint system including a first and a second airbag assembly;an airbag deactivation circuit, operatively engaging the first and thesecond airbag assemblies, including a switch having four switchpositions; switch actuation means, operatively engaging the switch, forselectively moving between the four switch positions; and switchlimiting means for selectively limiting the switch movement of theswitch actuation means to less than all of the four switch positions.14. The airbag restraint system of claim 13 wherein the switch actuationmeans includes a first key cylinder interchangeably connected to theairbag deactivation circuit and rotatable to effect movement between thefour switch positions, and the switch limiting means includes a rotationcontrol tab protruding from the key cylinder to limit the extent ofrotation of the key cylinder.
 15. The airbag restraint system of claim14 further including a third interchangeable bezel mounted adjacent thekey cylinder having indications thereon indicating the rotationallocation of the four switch positions.
 16. The airbag restraint systemof claim 14 wherein the rotation control tab limits the extent ofrotation of the key cylinder such that movement can only be effectedbetween two of the four switch positions and wherein a secondinterchangeable bezel is mounted adjacent the key cylinder, havingindications thereon indicating the rotational location of the two switchpositions.
 17. The airbag restraint system of claim 14 wherein therotation control tab limits the extent of rotation of the key cylindersuch that movement can only be effected between three of the four switchpositions and wherein a first interchangeable bezel is mounted adjacentthe key cylinder, having indications thereon indicating the rotationallocation of the three switch positions.
 18. An airbag restraint systemfor use in an automotive vehicle operable by a vehicle ignition keycomprising:an airbag restraint system including a first and a secondairbag assembly; an airbag deactivation circuit, operatively engagingthe first and the second airbag assemblies, including a switch havingfour switch positions; a first key cylinder interchangeably connected tothe airbag deactivation circuit and rotatable to effect movement betweenthe four switch positions; and switch limiting means, including arotation control tab protruding from the key cylinder, for selectivelylimiting the switch movement of the first key cylinder to less than allof the four switch positions.
 19. The airbag restraint system of claim18 wherein the rotation control tab limits the extent of rotation of thekey cylinder such that movement can only be effected between two of thefour switch positions and wherein a second interchangeable bezel ismounted adjacent the key cylinder, having indications thereon indicatingthe rotational location of the two switch positions.
 20. The airbagrestraint system of claim 18 wherein the rotation control tab limits theextent of rotation of the key cylinder such that movement can only beeffected between three of the four switch positions and wherein a firstinterchangeable bezel is mounted adjacent the key cylinder, havingindications thereon indicating the rotational location of the threeswitch positions.